gpkg_table_pragma(): Get information on a table in a GeoPackage (without returning the whole table).
gpkg_table(): Access a specific table (by name) and get a "lazy" dbplyr tbl_SQLiteConnection object referencing that table
gpkg_collect(): Alias for gpkg_table(..., collect=TRUE)
gpkg_tbl(): Alias for gpkg_table(..., collect=FALSE)(default) that always returns a tbl_SQLiteConnection object.
gpkg_rast(): Get a SpatRaster object corresponding to the specified table_name
gpkg_rast(): Get a SpatVector object corresponding to the specified table_name
gpkg_table_pragma(x, table_name = NULL, ...)
# S3 method for character
gpkg_table_pragma(x, table_name = NULL, ...)
# S3 method for SQLiteConnection
gpkg_table_pragma(x, table_name, ...)
# S3 method for geopackage
gpkg_table_pragma(x, table_name = NULL, ...)
gpkg_table(
x,
table_name,
collect = FALSE,
column_names = "*",
query_string = FALSE,
...
)
# S3 method for default
gpkg_table(
x,
table_name,
collect = FALSE,
column_names = "*",
query_string = FALSE,
...
)
gpkg_collect(x, table_name, query_string = FALSE, ...)
gpkg_tbl(x, table_name, ...)
gpkg_rast(x, table_name = NULL, ...)
gpkg_vect(x, table_name, ...)A geopackage object or character path to GeoPackage file
character. One or more table names; for gpkg_table_pragma() if table_name=NULL returns a record for each table. gpkg_table() requires table_name be specified
Additional arguments. In gpkg_table() arguments in ... are passed to dplyr::tbl(). For gpkg_table_pragma(), ... arguments are (currently) not used. For gpkg_rast() additional arguments are passed to terra::rast(). For gpkg_vect() additional arguments (such as proxy=TRUE) are passed to terra::vect().
logical. Materialize a data.frame object in memory? Default: FALSE requires 'dbplyr' package. TRUE uses 'RSQLite'.
character. Used only when collect=TRUE. A character vector of column names to select from table_name.
logical. Return SQLite query rather than executing it? Default: FALSE
gpkg_table(): A 'dbplyr' object of class tbl_SQLiteConnection
gpkg_collect(): An object of class data.frame
gpkg_tbl(): An object of class tbl_SQLiteConnection
gpkg_rast(): A 'terra' object of class SpatRaster
gpkg_vect(): A 'terra' object of class SpatVector (may not contain geometry columns)
tf <- tempfile(fileext = ".gpkg")
r <- terra::rast(system.file("extdata", "dem.tif", package = "gpkg"))
gpkg_write(r,
destfile = tf,
RASTER_TABLE = "DEM1",
FIELD_NAME = "Elevation")
gpkg_write(r,
destfile = tf,
append = TRUE,
RASTER_TABLE = "DEM2",
FIELD_NAME = "Elevation")
g <- geopackage(tf)
# inspect gpkg_contents table
gpkg_table(g, "gpkg_contents")
#> # Source: table<gpkg_contents> [2 x 10]
#> # Database: sqlite 3.45.0 [/tmp/Rtmpg33s4p/file1b013674eb59.gpkg]
#> table_name data_type identifier description last_change min_x min_y max_x
#> <chr> <chr> <chr> <chr> <chr> <dbl> <dbl> <dbl>
#> 1 DEM1 2d-gridded-co… DEM1 "" 2024-03-03… 6.01 49.7 6.27
#> 2 DEM2 2d-gridded-co… DEM2 "" 2024-03-03… 6.01 49.7 6.27
#> # ℹ 2 more variables: max_y <dbl>, srs_id <int>
gpkg_vect(g, "gpkg_contents")
#> class : SpatVector
#> geometry : none
#> dimensions : 0, 10 (geometries, attributes)
#> extent : 0, 0, 0, 0 (xmin, xmax, ymin, ymax)
#> source : file1b013674eb59.gpkg (SELECT)
#> coord. ref. :
#> names : table_name data_type identifier description last_change min_x
#> type : <chr> <chr> <chr> <chr> <chr> <num>
#> min_y max_x max_y srs_id
#> <num> <num> <num> <int>
# materialize a data.frame from gpkg_2d_gridded_tile_ancillary
library(dplyr, warn.conflicts = FALSE)
gpkg_table(g, "gpkg_2d_gridded_tile_ancillary") %>%
dplyr::filter(tpudt_name == "DEM2") %>%
dplyr::select(mean, std_dev) %>%
dplyr::collect()
#> # A tibble: 1 × 2
#> mean std_dev
#> <dbl> <dbl>
#> 1 324. 58.5
gpkg_disconnect(g)